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The advanced spintronic devices demand a new routine of manipulating spin states effectively with low power consumption, fast switching, and non-volatility. Here, a photovoltaic heterojunction structure of (Cu, Ta)/Co 40 Fe 40 B 20 /(Ta, Cu) on a p-n junction Si wafer is proposed. The saturation magnetizations (M s) tunability under sunlight illumination is decreased by ∼5–8 %. The first principle calculations reveal that the insert Cu or Ta layer promoted the photoelectron transmission, leading to a larger M s tunability. Moreover, the Ta layer also generates a barrier between the p-n junction and CoFeB to keep the photoelectrons in the CoFeB layer, creating a non-volatility and sunlight/electrical dual-regulated tri-state magnetization change. Element-resolved X-ray magnetic circular dichroism (XMCD) measurement is also performed to determine the diminished intrinsic magnetism and corresponding non-volatility during sunlight illumination. These fundings explore a new method of magnetic modulation further to expand the non-volatile, low-power sunlight-driven spintronics. [Display omitted] • Conventional current-driven spintronics exists heating issue, limiting device-minimization and increasing energy consumption. • Sunlight-induced magnetic change with non-volatility is realized by inserting the Ta layer. • We used the 5d bands of the Ta layer treated as a barrier to block the photoelectrons transfer to achieve the non-volatility. • Our work has an important guiding significance for the memory application of novel photovoltaic spintronic devices. [ABSTRACT FROM AUTHOR]

• The local lattice distortion appears at 90 K. • The local lattice distortion at Cu site in CuO 2 plane occurs with the inhomogeneous charge density distribution at 90 K. • Electron-lattice interaction play a key role in superconductivity of Sr 2 CuO 3 + δ. In order to study the relationship between local lattice distortion and superconductivity, we performed temperature dependent x-ray absorption fine structure (XAFS) on Sr 2 CuO 3 + δ powder sample (single phase with T c = 48 K). The temperature dependent Debye-Waller factor of Cu-O pair appears an anomalous upturn at 90 K and becomes drop around the superconducting transition temperature of ∼50 K. It means that local lattice distortion appears at 90 K. Furthermore, the analysis of temperature dependent X ray Absorption Near Edge Structure (XANES) shows that the R factor, which denotes the inhomogeneous charge density distribution, shows a sharp drop at 90 K. According to previous reports on other doped 214 cuprates, the above experimental results reveal that the local lattice distortion at Cu site in CuO 2 plane occurs with the inhomogeneous charge density distribution at 90 K. It indicates that the inhomogeneous charge density distribution may be caused by the local lattice distortion at Cu site before superconductive order formation, implying that electron-lattice interaction play a key role in superconductivity of Sr 2 CuO 3 + δ. [ABSTRACT FROM AUTHOR]